首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   2648861篇
  免费   187778篇
  国内免费   7859篇
耳鼻咽喉   36040篇
儿科学   87024篇
妇产科学   73665篇
基础医学   371120篇
口腔科学   71634篇
临床医学   238703篇
内科学   529772篇
皮肤病学   64258篇
神经病学   218999篇
特种医学   100955篇
外国民族医学   737篇
外科学   392676篇
综合类   50805篇
现状与发展   5篇
一般理论   987篇
预防医学   202366篇
眼科学   58016篇
药学   193330篇
  8篇
中国医学   5711篇
肿瘤学   147687篇
  2021年   22296篇
  2019年   22687篇
  2018年   31790篇
  2017年   24108篇
  2016年   27700篇
  2015年   30996篇
  2014年   42936篇
  2013年   63829篇
  2012年   84793篇
  2011年   89576篇
  2010年   53852篇
  2009年   51280篇
  2008年   82392篇
  2007年   87621篇
  2006年   89091篇
  2005年   85270篇
  2004年   82048篇
  2003年   79177篇
  2002年   76081篇
  2001年   129225篇
  2000年   132176篇
  1999年   111224篇
  1998年   31583篇
  1997年   28199篇
  1996年   28404篇
  1995年   27562篇
  1994年   25220篇
  1993年   23533篇
  1992年   85396篇
  1991年   81751篇
  1990年   78983篇
  1989年   76217篇
  1988年   69628篇
  1987年   68147篇
  1986年   63679篇
  1985年   60643篇
  1984年   45019篇
  1983年   38039篇
  1982年   22547篇
  1981年   20096篇
  1979年   39064篇
  1978年   27533篇
  1977年   23302篇
  1976年   21552篇
  1975年   22856篇
  1974年   26857篇
  1973年   25422篇
  1972年   23798篇
  1971年   22011篇
  1970年   20220篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
71.
72.
73.
Neu-Laxova syndrome (NLS) is a rare autosomal recessive syndrome, characterized by severe intrauterine growth retardation (IUGR), microcephaly, abnormal brain development, oedema and ichthyosis. It was first reported in 1971 by Neu et al. (Pediatrics 47: 610-612) and since then no more than 60 cases have been reported. A newborn girl delivered from a 29-year-old healthy mother was admitted to hospital with a thick membrane covering her body and dismorphic appearance. The diagnosis of NLS was made according to characteristic features. The syndrome is known to have a poor prognosis and the baby lived for 9 weeks. This case is one of the longest living cases of NLS and the fourth case reported from Turkey.  相似文献   
74.
The clinical outcome and appropriate management for patients showing 'borderline changes' on allograft biopsy after renal transplantation is still controversial. In an attempt to identify predictive factors of clinical outcome of patients with such lesions, we reviewed the clinical course of 91 patients with borderline changes. Multivariate analysis revealed significant and independent effects of histological stage (i + t < or = or > 2) and time to borderline changes (< or = or > 3 months after transplant) on serum creatinine levels at 1 year from borderline changes episodes (respectively, p = 0.04 and p = 0.02) and only a significant effect of time to borderline changes on serum creatinine levels at 2 years (p = 0.005). Renal function at 1 year and 2 years as 5- and 8-year graft survival were not significantly different in the group of patients treated with antirejection therapy (T group, n = 49) compared with the untreated group (UT group, n = 42). This study strongly suggests that borderline changes with histological score (i + t) > 2 and late episodes of borderline changes should be considered to be of poor prognosis.  相似文献   
75.
76.
77.
Primary chemotherapy administered to breast cancer patientsis the best model to identify baseline features able to predictwhich patients may be most likely to benefit or not from a cytotoxicregimen. In the March issue of Annals of Oncology two papersevaluated the predictive role of immunohistochemical p53 expressionon  相似文献   
78.
79.
PURPOSE: In children with locally advanced or recurrent malignant tumours, prognosis can be improved by regional deep hyperthermia (RHT) in combination with platin-based chemotherapy. However, because of the increasing number of patients that achieve long-time remission with this therapy, it is necessary to evaluate long-term sequelae of thermochemotherapy. During the years 1993-2004 one has observed avascular osteonecrosis (AON) of the femoral head after RHT in seven children with pelvic germ cell tumours or rhabdomyosarcomas. METHODS: Although AON may develop in patients with malignancies treated with chemo- or radiotherapy alone, RHT might nevertheless contribute to the occurrence of AON. In order to determine potential risk factors for AON after RHT, this study analysed the relationship of AON to the patient's age, medical history and treatment parameters such as thermal dose equivalent and power output. RESULTS AND CONCLUSIONS: In the present study AON was associated with young age as well as intensity of hyperthermia indicated by high power levels that exceed 20 W per kg body weight and/or application of eight or more heat sessions as well as additional radiotherapy. Based on this observation, it was assumed that an optimized three dimensional thermal field modelling may be helpful to avoid hazardous temperatures in the femoral heads during RHT treatment and to reduce AON of the femoral heads.  相似文献   
80.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号